Process of utilizing nitrous gases.



' quantity of nitrite.

, human srnirns rarnnir ormcn KRISTIAN BIRKELAND, OF CHRISTIANIA,NORWAY.

ilddflldd. Ho Drawing.

To all whom it may concern:

Be it known that I, :KRISTIAN Bimcnrnnn, a sub ect ot the King ofNorway, residlng at Christiania, horway, have lnvented certain new anduseful Improvements in Processes of Utilizing Nitrous Gases; and I dohereby declare the followin to be a full, clear, and exact descriptionof the invention, such as will enable others skilled in -the art towhich it appertains to make and use the same.

My invention relates to a process of absorbing nitrous gases, for thepurpose of chemically combining the nitrous gases in such a way as toobtain valuable products. 15 for agricultural and other purposes.

According to my invention I use as obsorbent a cyanamld' (preferablycyanamid of calcium).

When nitrous gases containing fumes of nitric acid, mixed with othernitrogen oxids, air and Water '(steam), in proper proportions, arebrought into contact with cyanamid of calcium, a chemical reaction willtake place; This chemical reaction may be expressed theoretically by thefollowing equations:

As Will-be seen fromthe first of these equations, stituting a compound.of calcium nitrate and ammonium nitrate. To this comes in the practicalembodiment of the process, when differentoxid's of nitrogen are present,a

he percent a e of nitrogen of the compound will in-t I the process be uWard of 25%, and by this process I succee in making use of all thevaluable properties of the cyanamid of calcium, at the sametime avoidingthe bad properties of this substance, for instance its propensity todeveloping hydric phos hid. The compound thus formed. is comp etelypreservable and has properties making it a ver valuable fertilizer, the,obtaining of sue products being oneof the objectsof my inrention, 1

I have generaliyused the cyanamid of cal- Specification of LettersPatent. Application. filed August 9, 1907.

there is formed a product con'- e practical embodiment of presence ofWater.

PROCESS OF UTILIZING NI'EROUS GASES.

Patented lBeb. t, ram. serial No. 387,814.

cium mixed with Water to a thick paste. It

may, however, also be used dry, in which case steam is preferably blowninto the absorption chamber,

Another object of my invention is to use the compound formed in the wayabove specified-(and containing for instance calcium nitrate andmanufacturing nitric acid, (whereby is simultanepusly obtained certainvaluable byproducts),aud for extracting the ammonium nitrate. .lfiOI'this purpose I preferably carry out my process in the following manner:To a solution of the above mentioned product is added ammonium the limeis deposited in form of hydrated sulfate of lime, and the solution leftwill essentially consist of annnonium nitrate, which in itself is avaluable product.- In order to produce nitric acid of ammonium nitrateby evaporation and add sulfuric acid, whereupon I distil the mixturethus obtained, is distilled cit, while ammonium sulfate is left. Thisammonium sulfate may partly be used in carrying out the above process,as explained in the foregoing, and the remain ammonium nitrate) forsulfate, whereby whereby nitric acid der may be disposed of as avaluable for I may of course also process without first de ositing thehydrated sulfate of lime by ai of ammonium sulfate, merely treating thecompound in uestion with sulfuric acid and dlstilling o the nitric acid.I in this case obtain as a byproduct a mixture of gypsum and ammoniumsulfate, ivhich also constitutes a valuable fertilizer.

carry out the above I claim.

'1. A process of utilizing nitrous gases comprising the step of bringingsaid gases into, contact with an absor )tion material containing acyanamid in t e presence of ivater.

2. A process comprisingthe into contactwith calcium cyanamid in the 3.A. process of utilizing nitrous gases comprising the step of leadingnitrous gases of the class set forth into contact with calcium-cyanamidin the presence of water,

dissolving the product in Water and adding of utilizing nitrous gasesstep of bringing said gases thereto ammommn sulfate, thereby preclpi- 1toting column-sulfate and. producmg a sol.ution of ammomum mtmte, whlch1s concentrafed by evaporation, treatlug said ammo mum-sulfate wlthsulfurlc 101d to'obtamnltrle acld and :unmomum-sulfate.

In testimony that I claim the foregoi ng as 15) iny inventiom I havesigned my name in presence of two subscrlbmg wltnesses.

KRIST'KAN B IRKELAND \Vii messes v HEM?! Bommwwu,

J. E. VAcH

